Wash and iron fabric. Refold the fabric along the original fold. Position cutting mat so that the 18-inch length parallels the edge of the table. Lay the fabric out on the cutting mat with the fold off the left side of the mat. Measure 18 inches from the fold and make a mark on your fabric. Repeat several more times down the length of the fabric. Making sure the marked fabric is on the cutting mat, line up the ruler with the marks and trim off the excess. Turn the fabric and square up the two original edges of the fabric, being careful to retain a full yard of length.
Open fabric and repress to remove any fold lines. Fold the fabric square in half on the diagonal and press along the fold. Be careful not to stretch the fabric while pressing. Open the fabric triangle up and using your fabric scissors, cut along the diagonal fold.
Lay out one triangle, right side of the fabric facing up, with the diagonal running from the upper right corner to the lower left. Lay the second triangle on top, right side of the fabric facing down, and with the diagonal running from the upper left corner to the lower right. Make a 1/4-inch seam along the upper edge. This will be along the straight of the grain, or with the weave of the fabric. Press the seam to one side using your iron. The result is a trapezoid-shaped piece of fabric.
Lay out the fabric trapezoid right side down and with one bias edge at the top. The bias edge runs diagonal to the weave of the fabric and resulted from the original diagonal fold that you cut with your scissors. Near one of the diagonal edges, measure straight down from the bias edge 2 1/4 inches and make a mark on your fabric. Make sure the mark is along the edge. Be sure to measure from the upper edge of the fabric and not along the diagonal. Pick up the fabric and align the mark with the seam junction from your first seam. Be sure to have the right sides of the fabric together. Align the straight of the grain edges, those being the edges which run with the weave of the fabric. Retaining your alignment with your mark, make a 1/4-inch seam along the straight of the grain. When done you will have a tube with a tail at the top and bottom. The top and bottom edges should be bias edges. Gently press the second seam to follow the first.
Lay your tube on a table with your original mark showing and to your left. Lay your ruler along the bias edge, matching up with your mark and measuring 2 inches from the edge of the tube. Approximately 1/4 inch was lost when making the second seam. Mark with your pencil directly on the fabric the 2-inch line. Pick up the ruler and adjust your fabric to continue marking in 2-inch increments around the tube. Once you have gone around once, you will find that you don't come back to exactly where you started: your marks should spiral around the tube. Align the marked line using your ruler and continue marking down and around the length of the tube. Using your fabric scissors, cut along the marked line to give you a long strip of fabric. Gently press with the iron the strip in half lengthwise with wrong sides of the fabric together.